Vending machines are a popular way to market and sell consumable items. Vending machines use various mechanisms and moving parts, such as gears, levers, ratchets, motors, and solenoids to properly vend the selected item. Certain consumable items, such as ice cream, must be stored in the vending machine in a certain temperature range to maintain the desired characteristics of the consumable item. When the mechanisms and moving parts of the vending machine are exposed to temperatures required to maintain certain consumable items such as ice cream in their desired state, mechanical failure is more likely.
One known way to decrease such mechanical failure is to store the consumable product in a cooled article storage compartment that is separated from the remainder of the vending machine cabinet by a thermal barrier. The thermal barrier can be opened when the article is selected and removed from the storage compartment and then closed when the vending cycle is completed. An example of such an apparatus is disclosed in U.S. Pat. No. 5,240,139 (“the '139 patent) to Chirnomas. The apparatus disclosed by Chirnomas contains a freezer storage compartment with a thermal barrier for maintaining a frozen environment in isolation of the ambient temperature air filling the remaining interior space of the vending machine. The apparatus disclosed by the '139 patent to Chirnomas further contains a mechanism for opening and closing the thermal barrier, a vacuum picker for removing a selected article from the storage freezer compartment, and a controller for controlling the vacuum picker and the opening and closing mechanism. The vacuum picker is located outside the freezer compartment in between operating cycles and enters the freezer compartment only when removing an article to be dispensed.
The apparatus disclosed by the '139 patent to Chirnomas prevents the moving mechanisms from being constantly exposed to freezing temperatures inside the vending machine. However, the apparatus disclosed by Chirnomas creates another problem. During normal machine operation, the thermal barrier is opened and closed many times, which exposes the cooled article storage compartment and the articles being stored in the cooled article storage compartment to the ambient air. Such exposure to ambient air is undesirable because over time it can degrade the quality of the frozen articles. This is particularly true when the stored articles include cryogenically frozen and free flowing particles of ice cream, which can sinter, or stick together, when ambient air is repeatedly introduced into the cooled article storage compartment by the thermal barrier being opened during normal operation. Methods of manufacture of such cryogenically frozen and free flowing particles of ice cream are described, for example, in U.S. Pat. No. 6,349,549 (“the '549 patent) to Angus, et al. and U.S. Pat. No. 5,126,156 (“the '156 patent) to Jones. Since one of the highly desirable characteristics of the frozen ice cream particles is their free flowing character, it is important that the particles are kept in a free flowing state before they are purchased by the consumer in a vending environment. An additional problem with moist ambient air being introduced into the cooled storage chamber is that moist air tends to form frost that can build up on the internal walls of the storage compartment and reduce the internal size of the storage compartment and adversely affect the positioning of the stored articles and the thermal and operational efficiency of the cooling units.
The above described problems of moist ambient air entering a cooled storage compartment in a vending machine and adversely affecting the stored article and cooling chamber are discussed in U.S. Pat. No. 7,118,009 (“the '009 patent) to Chirnomas. The solution disclosed in the '009 patent to Chirnomas is a storage compartment that is divided into a plurality of sub-compartments, each of which has a displaceable flap that covers the dispensing end of the sub-compartment. Each displaceable flap operates individually with respect to each sub-compartment, thereby allowing articles in the sub-compartments to pass therethrough during the dispensing operation.
The plurality of individual flaps disclosed in the '009 patent to Chirnomas creates additional problems. First, when the storage compartments are cooled to very cold temperatures, for example −40 degrees Centigrade to store frozen free flowing ice cream beads, the flaps are exposed to very cold temperatures on a relative constant basis. These very cold storage temperatures have a tendency to adversely affect the flexibility and operability of the individual flaps. The individual flaps must remain flexible enough so that the suction force holding the article to the picker head is not overcome. When the very cold storage temperatures create enough rigidity in the flaps such that the suction force holding the article to the picker head is overcome, the vacuum picker is unable to remove the article from the storage cabinet. If the flexible flaps become brittle and break or otherwise degrade over time as they are exposed to cold temperatures, their ability to serve as an effective thermal barrier is compromised or eliminated. An additional problem is that the plurality of individual flexible flaps in the vending machine adds a multitude of additional moving pieces that are potentially prone to failure. The failure rate of the additional moving pieces is increased due to exposure to the frozen environment. The reintroduction of moving parts into the frozen environment recreates the very problem that U.S. Pat. No. 5,240,139 to Chirnomas sought to eliminate (separating the moving parts from the frozen environment).
U.S. Pat. No. 6,481,226 (the '226 patent) to Jones discloses a vending machine for serving extremely cold frozen product such as frozen and free flowing ice cream beads and pieces. The problem sought to be solved by the '226 patent is how to maintain temperatures cold enough in a vending machine storage cabinet to preserve the free flowing nature and integrity of frozen and free flowing ice cream product. The '226 patent discloses an invention directed toward modifying a vending machine to store product at a temperature no greater than −40 degrees Celsius by replacing the compressor with a compressor having higher compression, replacing existing refrigerant with a more efficient refrigerant, increasing the length of the capillary tube, and providing a thermostat capable of achieving a −40 Celsius set point. The disclosed preferred embodiment includes a safety switch that is operable to disable the vending machine from dispensing product if the temperature exceeds the set point. The '226 patent further discloses a freezer chest with a single lid that overlies the top of the freezer chest and that is hinged along one edge for movement between the open and closed positions. The single lid remains closed to maintain the temperature within the freezer chest to its coldest possible temperature until the vending machine is in active operation. When a user selects an article for dispensing, the single lid overlying the freezer chest is opened by a motor so that the motorized serving arm may retrieve ice cream product from within the freezer chest.
U.S. Patent Application Publication 2005/0211720 (“the '720 patent application”) to Chirnomas discloses a method and apparatus for storing articles for use with an article handling device. FIG. 5 and FIG. 9 of the '720 patent application illustrate a multiple storage area arrangement where a single vacuum picker serves adjacent storage areas. FIG. 5 illustrates that each storage area has a door. However, the '720 patent application does not disclose how the illustrated doors open (whether hinged, slidable, foldable, etc.) and whether the doors are capable of opening independently from one another. The '720 Published patent application also does not disclose any control mechanism that controls the opening and closing of the doors in relation to the location or operation of the article vacuum picker. The '720 patent app. discloses that the multiple storage areas may be maintained at different temperatures whereby one storage area may have an ambient temperature and the other storage areas may be cooled to a refrigerated temperature or freezing temperature. FIG. 5 and FIG. 9 of the '720 patent app. illustrate and disclose a single cooling unit.
The above described prior art discloses vending machine apparatus and methods capable of storing, selecting, and dispensing articles, including frozen and free flowing pieces of ice cream. However, the above-described prior art apparatus and methods still suffer from a number of problems. One problem is how to effectively prevent ambient and moist air from mixing with the cooled and dry air existing in the cooled storage compartments. The '139 patent to Chirnomas discloses thermal separating means being operative to prevent heat transfer between the cooled storage compartments and the remainder of the interior of the outer cabinet's interior. The thermal separating structure disclosed by the '139 patent consists of (1) sliding panels positioned in sliding door tracks (FIG. 3 in the '139 patent), (2) a multi-part cover constructed with numerous panel members that slide over or under adjacent members (FIG. 11 in the '139 patent), (3) a plurality of hinged members that fold up against one another (FIG. 12 in the '139 patent), (4) a single unit that is connected by at least one hinge to the freezer compartment and that opens in a vertically arcing motion (FIG. 13 in the '139 patent), and (5) a single flexible member that slides in a track (FIG. 14 in the '139 patent). Each of these disclosed structures suffers from the problem of allowing ambient air to mix with the air in the cooled storage compartments when the thermal barrier is displaced during normal vending operation. For example, the single unit that is connected by at least one hinge exposes all the cooled storage compartments to ambient air when it is opened in a vertically arcing motion. The remaining structures that displace by sliding or folding also may expose all the cooled storage compartments to ambient air during normal vending operation. For example, the sliding panels positioned in the sliding door tracks in FIG. 3 of the '139 patent must expose all the cooled storage compartments to ambient air when sliding to open the cooled storage department disposed closest to the vertical rise in the sliding door track. Each of the other sliding or folding structures disclosed in the '139 patent also suffers from this problem.
The '226 patent to Jones discloses a freezer chest with a single lid that overlies the top of the freezer chest and that is hinged along one edge for movement between the open and closed positions. This single lid suffers from the same problems as the single unit that opens in a vertically arcing motion in the '139 patent in that all the cooled storage compartments are exposed to ambient air when the single lid disclosed in the '226 patent is opened.
The '720 Published patent application to Chirnomas discloses a multiple storage area arrangement where each storage area has a door. However, as previously stated the '720 Published patent application does not disclose how the illustrated doors open (whether hinged, slidable, foldable, etc.), whether the doors are capable of opening independently from one another, and does not disclose any control mechanism that controls the opening and closing of the doors in relation to the location or operation of the article vacuum picker.
The '009 patent to Chirnomas discloses a plurality of individual flexible flaps designed to keep the ambient air from mixing with the individual storage compartments during the vending cycle. However, as discussed above, when the flexible flaps become brittle and break or otherwise degrade over time as they are exposed to cold temperatures, their ability to serve as an effective thermal barrier is compromised or eliminated. Further, the plurality of individual flexible flaps in the vending machine adds a multitude of additional moving pieces that are potentially prone to failure, particularly due to their exposure to the frozen environment.
A second problem is that a cooling unit in a vending machine may fail, thereby potentially resulting in spoilage to refrigerated and frozen articles being stored in the storage department. The '226 patent to Jones discussed previously discloses a vending machine that includes a safety switch that is operable to disable the vending machine from dispensing product if the temperature exceeds the set point. However, the '226 patent discloses a freezer chest with only a single lid that overlies the top of the freezer chest and that is hinged along one edge for movement between the open and closed positions. If the temperature exceeds the set point, the entire vending machine is disabled.
A third problem is that the displaceable thermal barrier may not open as a result of a failure of the opening mechanism, the displaceable thermal barrier becoming frozen shut due to a build up of ice, or due to some other failure. The vending machine disclosed in the '139 patent to Chirnomas becomes incapable of vending product if the thermal separating barrier is broken, frozen shut, or is otherwise disabled. The vending machine disclosed in the '139 patent to Chirnomas also is incapable of vending product if the opening mechanism is broken or otherwise disabled.
In light of the aforementioned problems existing in the prior art, there is a need for a more effective thermal barrier that results in less ambient air entering the cooled storage compartments during the vending cycle and that exposes less of the stored articles in the cooled storage compartments to ambient air during a vending cycle. There also is a need for a vending machine that can vend cooled and frozen stored articles when a displaceable thermal barrier opening mechanism breaks or fails or when a displaceable thermal barrier cannot otherwise be opened. There also is a need for a vending machine that can vend cooled and frozen stored articles when a cooling unit fails.
What is further needed is a vending machine with a control mechanism capable of recognizing when a displaceable thermal barrier cannot be opened, that can inform and warn the user that articles located in such storage compartments are unavailable for purchase but that other articles stored in other cooled storage compartments are still available for purchase, and that can direct the article extractor to select articles from storage compartments whose displaceable thermal barriers can be opened.
What is further needed is a vending machine with a control mechanism capable of recognizing when a cooling unit has failed, that can inform and warn the user that articles located in storage compartments with failed cooling units are unavailable for purchase but that other articles stored in other cooled storage compartments with properly functioning cooling units are still available for purchase, and that can direct the article extractor to select articles from storage compartments whose cooling units are functioning properly.